Migraines are the third most common illness in the word, but their underlying causes and how to treat them are still largely a mystery to doctors. Now, NPR reports that an alternative therapy may be on the way for migraine sufferers dissatisfied with pills that only mask the symptoms. A new type of shot has the potential to relieve migraines for up to three months while causing hardly any side effects.
Since the 1980s, scientists have studied how a protein called calcitonin gene–related peptide (CGRP) relates to migraine episodes. Research shows that people experiencing the throbbing head pain, vertigo, and light sensitivity that come with migraines have high levels of this protein in their blood.
When CGRP is injected into the bloodstream of someone who's susceptible to migraines, it triggers these intense symptoms, researchers found. But when people who don't normally get migraines receive a shot of it, their side effects are mild pain at worst. Further studies in mice demonstrated that by blocking CGRP in the brain, researchers could stop their migraine-like symptoms from developing.
The first CGRP-blocking treatment for humans came in the form of a pill in 2011. Though the clinical trials seemed promising, the medication never made it into pharmacies due to its possible effects on the liver. The latest version of the therapy doesn't interact with the liver at all. Instead, monoclonal antibodies, the same immune molecules often used in cancer treatments, are injected directly into the blood. They bypass the organ to block CGRP in the brain.
Four pharmaceutical companies have developed CGRP-blocking medicine for migraines, and based on their clinical trials, the shots relieve pain for periods ranging from one to two days to three months at a time. And unlike current treatments on the market, which include antidepressants and epilepsy medication as well as prescription pain relievers, the most noticeable side effect is pain at the injection site.
Two of the companies developing the drug, Amgen (in collaboration with Novartis) and Teva Pharmaceuticals, will know in June whether the drug has been approved by the FDA, while Eli Lilly and Alder Biopharmaceuticals plan to submit their medications for approval later in 2018. If they are made available to the public, the treatments will likely be pricey, falling in the range of $8000 to $18,000 a year for patients who get the shots once a month. And though there are hardly any side effects in the short term, the drugs haven't been studied enough for long-term side effects to emerge. For those reasons, the shots may work best as a last resort for migraine sufferers for whom all other treatments have failed.